Semiconductor device

ABSTRACT

A semiconductor device includes a semiconductor element, a lead frame, a bridge member, and a sealing resin. The semiconductor element has first and second surfaces opposite from each other, and has first and second electrodes respectively exposed on the first and second surfaces. The lead frame includes a mounting portion and a non-mounting portion divided from the mounting portion. The mounting portion has a mounting surface to which the semiconductor element is mounted and the first electrode is electrically connected, and an opposite surface opposite from the mounting surface. The bridge member electrically connects the second electrode and the non-mounting portion. The sealing resin has electric insulation, has a thermal conductivity of 2.2 W or more, and covers the semiconductor element, the lead frame, and the bridge member in a state where the opposite surface of the mounting portion is exposed from the sealing resin.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a continuation application of InternationalPatent Application No. PCT/JP2020/021510 filed on Jun. 1, 2020, whichdesignated the U.S. and claims the benefit of priority from JapanesePatent Application No. 2019-128732 filed on Jul. 10, 2019. The entiredisclosures of all of the above applications are incorporated herein byreference.

TECHNICAL FIELD

The present disclosure relates to a semiconductor device.

BACKGROUND

There has been known a semiconductor device including a semiconductorelement, a heat sink electrically and thermally connected to thesemiconductor element, and a sealing resin covering the semiconductorelement and the heat sink in a state where a surface of the heat sinkopposite from the semiconductor element is exposed from the sealingresin.

SUMMARY

The present disclosure provides a semiconductor device including asemiconductor element, a lead frame, a bridge member, and a sealingresin. The semiconductor element has first and second surfaces oppositefrom each other, and has first and second electrodes respectivelyexposed on the first and second surfaces. The lead frame includes amounting portion and a non-mounting portion divided from the mountingportion. The mounting portion has a mounting surface on which thesemiconductor element is mounted and the first electrode is electricallyconnected, and an opposite surface opposite from the mounting surface.The bridge member electrically connects the second electrode and thenon-mounting portion. The sealing resin has electric insulation, has athermal conductivity of 2.2 W or more, and covers the semiconductorelement, the lead frame, and the bridge member in a state where theopposite surface of the mounting portion is exposed from the sealingresin.

BRIEF DESCRIPTION OF DRAWINGS

Objects, features and advantages of the present disclosure will becomeapparent from the following detailed description made with reference tothe accompanying drawings. In the drawings:

FIG. 1 is a plan view showing a schematic configuration of asemiconductor device according to an embodiment;

FIG. 2 is a cross-sectional view of the semiconductor device taken alongline II-II in FIG. 1;

FIG. 3 is a graph showing heat dissipation characteristics of thesemiconductor device according to the embodiment and a semiconductordevice according to a comparative example;

FIG. 4 is a cross-sectional view showing a schematic configuration of asemiconductor device according to a first modification; and

FIG. 5 is a plan view showing a schematic configuration of asemiconductor device according to a second modification.

DETAILED DESCRIPTION

A semiconductor device according to an example includes aheat-generating element, a terminal and a first heat sink electricallyand thermally connected to one surface of the heat-generating element, asecond heat sink electrically and thermally connected to the othersurface of the heat-generating element, and a sealing resin body thatseals these components. The first heat sink has a facing surface thatfaces the terminal and an opposite surface that is opposite from thefacing surface and is exposed from the sealing resin body. The secondheat sink has a facing surface that faces the heat-generating elementand an opposite surface that is opposite from the facing surface and isexposed from the sealing resin body.

In the semiconductor device described above, the opposite surfaces ofthe first heat sink and the second heat sink are exposed from thesealing resin body as heat dissipation surfaces. Therefore, thesemiconductor device needs to be further provided with an insulatingmember such as a gel in order to secure electric insulation.

A semiconductor device according to an aspect of the present disclosureincludes a semiconductor element, a lead frame, a bridge member, and asealing resin. The semiconductor element has a first surface and asecond surface opposite from each other, and has a first electrodeexposed on the first surface and a second electrode disposed on thesecond surface. The lead frame includes a mounting portion and anon-mounting portion divided from the mounting portion. The mountingportion has a mounting surface on which the semiconductor element ismounted and the first electrode is electrically connected and anopposite surface opposite from the mounting surface. The bridge memberhas conductivity and electrically connects the second electrode and thenon-mounting portion. The sealing resin has electric insulation, has athermal conductivity of 2.2 W or more, and covers the semiconductorelement, the lead frame, and the bridge member in a state where theopposite surface of the mounting portion is exposed from the sealingresin.

In the semiconductor device according to the aspect, since the bridgemember is covered with the sealing resin without being exposed, electricinsulation can be ensured. Further, in the semiconductor deviceaccording to the aspect, since the thermal conductivity of the sealingresin is 2.2 W or more, heat dissipation can be ensured.

Hereinafter, multiple embodiments of the present disclosure will bedescribed with reference to the drawings. In each embodiment, portionscorresponding to those described in the preceding embodiment are denotedby the same reference numerals, and redundant descriptions will beomitted in some cases. In each embodiment, in a case where only a partof the configuration is described, another preceding embodiment can bereferenced to and applied to the other parts of the configuration.Hereinafter, three directions perpendicular to each other are denoted asan X direction, a Y direction, and a Z direction.

A semiconductor device 100 according to an embodiment of the presentdisclosure will be described with reference to FIGS. 1, 2, and 3. Asshown in FIGS. 1 and 2, the semiconductor device 100 includes twosemiconductor elements 1 and 2, two lead frames 30 and 40, two clips 51and 52, and a sealing resin 7. The present embodiment adopts thesemiconductor device 100 including two semiconductor elements 1 and 2.Along with this, the semiconductor device 100 includes two lead frames30 and 40 and two clips 51 and 52. Further, the semiconductor device 100includes two wires 61 and 62.

However, the present disclosure is not limited to this example. Thesemiconductor device 100 needs to include at least one semiconductorelement, the same number of lead frames as the number of semiconductorelements and the same number of clips as the number of semiconductorelements.

In FIG. 1, a part of the sealing resin 7 is omitted in order to simplifythe drawing and make each component easy to understand. That is, in FIG.1, the portion of the sealing resin 7 that covers the two semiconductorelements 1 and 2, the two lead frames 30 and 40, the two clips 51 and52, and the two wires 61 and 62 is omitted.

As an example, a metal oxide film semiconductor field effect transistor(MOSFET) is adopted as each of the semiconductor elements 1 and 2.However, the present disclosure is not limited to this example, and aninsulated gate bipolar transistor (IGBT) or the like can also be adoptedas each of the semiconductor elements 1 and 2. As another example, areverse conduction (RC)-IGBT in which an IGBT and a diode are integratedcan also be adopted as an each of the semiconductor elements 1 and 2.Further, as each of the semiconductor elements 1 and 2, for example, asemiconductor element having Si as a main component or a semiconductorelement having SiC as a main component can be adopted.

The first semiconductor element 1 includes a first substrate 11 having afirst surface and a second surface opposite from each other, a firstdrain electrode 14 exposed on the first surface of the first substrate11, and a first source electrode 12 and a first gate electrode 13exposed on the second surface of the first substrate 11. The first drainelectrode 14 is formed on substantially the entire area of the firstsurface of the first substrate 11. On the other hand, the first sourceelectrode 12 and the first gate electrode 13 are partially formed on thesecond surface of the first substrate 11.

The first substrate 11 has, for example, a rectangular shape in an XYplane and has a thickness in the Z direction. In the present embodiment,as an example, the first substrate in which the Y direction is alongitudinal direction and the X direction is a lateral direction isadopted.

The first semiconductor element 1 may be formed with a temperaturesensor, a current sensor, or the like. In this case, in thesemiconductor element 1, a pad electrically connected to the temperaturesensor or the current sensor is formed on the same surface as the firstsource electrode 12 and the first gate electrode 13.

The second semiconductor element 2 includes a second substrate 21 havinga first surface and a second surface opposite from each other, a seconddrain electrode exposed on the first surface of the second substrate 21,a second source electrode 22 and a second gate electrode 23 exposed onthe second surface of the second substrate 21. The second semiconductorelement 2 has a structure similar to the first semiconductor element 1.Therefore, regarding the second semiconductor element 2, the descriptionof the first semiconductor element 1 can be referred to.

The first semiconductor element 1 and the second semiconductor element 2correspond to semiconductor elements. The first drain electrode 14 andthe second drain correspond to first electrodes. The first sourceelectrode 12 and the second source electrode 22 correspond to secondelectrodes.

The first read frame 30 has a first source terminal 31, a first drainterminal 32, and a first signal terminal 33. The first lead frame 30 maycontain a conductive material as a main component. The conductivematerial is a metallic material such as Cu, Fe, or an alloy thereof. Thefirst source terminal 31, the first drain terminal 32, and the firstsignal terminal 33 are separated from each other.

The first drain terminal 32 has a mounting surface S12 on which thefirst semiconductor element 1 is mounted. More specifically, the firstdrain terminal 32 is a portion where the first semiconductor element 1is mounted and the first drain electrode 14 is electrically connected.The first drain terminal 32 is electrically connected to the first drainelectrode 14 via a conductive connecting member such as solder.Therefore, the first semiconductor element 1 is mounted to the firstdrain terminal 32 by electrically connecting the first drain electrode14 and the first drain terminal 32 via the conductive connecting member.In the present embodiment, solder is used as the conductive connectingmember.

The drain terminal 32 has an opposite surface S11 that is opposite fromthe mounting surface, and the opposite surface S11 is exposed from thesealing resin 7. Therefore, in addition to the function as electricalwiring, the first drain terminal 32 also has a function as a heat sinkfor dissipating heat generated from the first semiconductor element 1.Therefore, the opposite surface S11 can be said to be a heat dissipationsurface. For the mounting surface S12 and the opposite surface S11, forexample, a flat surface can be adopted.

The first drain terminal 32 corresponds to a mounting portion. Further,the first drain terminal 32 can be said to be an island.

The first source terminal 31 is electrically connected to the firstsource electrode 12 via the first clip 51. In this way, the first sourceterminal 31 is not mounted with the first semiconductor element 1, andis electrically connected to the first semiconductor element 1 (firstsource electrode 12) via the first clip 51.

For example, the first clip 51 may contain a conductive material such asa metal material such as Cu, Fe or an alloy thereof as a main component.The first clip 51 includes a first element facing portion 51 a facingthe first source electrode 12, a first terminal facing portion 51 bcorresponding to the first source terminal 31, and a first connectingportion 51 c that connects the first element facing portion 51 a and thefirst terminal facing portion 51 b. The first element facing portion 51a, the first terminal facing portion 51 b, and the first connectingportion 51 c are configured as an integral body.

The first element facing portion 51 a is electrically connected to thefirst source electrode 12 via solder. Similarly, the first terminalfacing portion 51 b is electrically connected to the first sourceterminal 31 via solder. In this way, in the first semiconductor element1, the first source electrode 12 and the first source terminal 31 areelectrically connected via the first clip 51.

In the present embodiment, as an example, the first clip 51 which has arectangular shape in the XY plane and has a thickness in the Z directionis adopted. Further, in the present embodiment, as an example, the firstclip 51 in which the first connecting portion 51 c faces an end portionof the first semiconductor element 1 and the first drain terminal 32 isadopted. Further, in the present embodiment, as shown in FIG. 2, thefirst clip 51 in which a thickness of the first connecting portion 51 cis thinner than a thickness of the first element facing portion 51 a isadopted.

As a result, the semiconductor device 100 can easily secure aninsulation distance between the first drain terminal 32 and the firstclip 51. Further, since a heat capacity on the first semiconductorelement 1 can be increased as compared with a case where the firstelement facing portion 51 a has the same thickness as the firstconnecting portion 51 c, the heat dissipation of the semiconductordevice 100 can be improved.

The first source terminal 31 corresponds to a non-mounting portion.Further, the first clip 51 corresponds to a bridge member.

The first signal terminal 33 is electrically connected to the first gateelectrode 13 via the first wire 61.

Therefore, one of the first signal terminals 33 is electricallyconnected to the first gate electrode 13. Another one of the firstsignal terminals 33 is electrically connected to the pad, which iselectrically connected to the temperature sensor or the current sensor,via the first wire 61.

In the first lead frame 30, a surface of the first source terminal 31 towhich the first terminal facing portion 51 b is connected and surfacesof the first signal terminals 33 to which the first wire 61 is connectedare flush with the mounting surface S12 of the first drain terminal 32.That is, it can be said that the surface of the first source terminal 31to which the first terminal facing portion 51 b is connected and thesurfaces of the first signal terminals 33 to which the first wire 61 isconnected are formed on an XY plane passing through the mounting surfaceS12. Similarly, an opposite surface of the surface of the first sourceterminal 31 to which the first terminal facing portion 51 b is connectedand opposite surfaces of the surfaces of the first signal terminals 33to which the first wire 61 is connected are flush with the oppositesurface S11 of the first drain terminal 32.

Therefore, the opposite surface S11, the opposite surface of the surfaceof the first source terminal 31 to which the first terminal facingportion 51 b is connected, and the opposite surfaces of the first signalterminals 33 to which the first wire 61 is connected can also becorrectively referred to as the opposite surfaces S11.

Further, the second lead frame 40 has a mounting surface and an oppositesurface in a manner similar to the first lead frame 30. Therefore, inthe following, the portion described as the opposite surfaces S11without particular indication indicates the opposite surfaces S11 of thefirst lead frame 30 and the second lead frame 40.

The second lead frame 40 has a second source terminal 41, a second drainterminal 42, and second signal terminals 43. The second lead frame 40has a configuration similar to the first lead frame 30. Therefore,regarding the second lead frame 40, the description of the first leadframe 30 can be referred to.

The second clip 52 has a second element facing portion 52 a, a secondterminal facing portion 52 b, and a second connecting portion 52 c. Thesecond clip 52 has a configuration similar to the first clip 51.Therefore, regarding the second clip 52, the description of the firstclip 51 can be referred to.

The second wire 62 has a configuration similar to the first wire 61.Therefore, regarding the second wire 62, the description of the firstwire 61 can be referred to.

The sealing resin 7 contains an electrically insulating resin and afiller having a higher thermal conductivity than the electricallyinsulating resin as constituent materials. That is, the sealing resin 7has the filler embedded in the electrically insulating resin. As theelectrically insulating resin, for example, an epoxy resin or the likecan be adopted. On the other hand, as the filler, inorganic particlessuch as alumina can be adopted. The sealing resin 7 is formed, forexample, by injection molding using a mold.

The sealing resin 7 integrally covers the semiconductor elements 1 and2, the lead frames 30 and 40, the clips 51 and 52, and the wires 61 and62. It can be said that the sealing resin 7 seals these components whilebeing in contact with these components. Further, as described above, thesemiconductor elements 1 and 2, the lead frames 30 and 40, the clips 51and 52, and the wires 61 and 62 shown in FIG. 1 are sealed with thesealing resin 7. The sealing resin 7 has a rectangular shape on the XYplane.

As shown in FIG. 2, the sealing resin 7 has a first surface S1 and asecond surface S2 opposite to the first surface S1. For the firstsurface S1 and the second surface S2, for example, flat surfaces can beadopted. Further, it can be said that the first surface S1 and thesecond surface S2 are formed along the XY plane.

As shown in FIG. 2, the sealing resin 7 covers the semiconductorelements 1 and 2, the lead frames 30 and 40, the clips 51 and 52, andthe wires 61 and 62 in a state where the opposite surfaces S11 of thedrain terminals 32 and 42 are exposed. In the lead frames 30 and 40, theentire area of the opposite surfaces S11 is exposed from the sealingresin 7. The first surface S1 is formed flush with the opposite surfacesS11.

The sealing resin 7 has an electrical insulating property and a thermalconductivity of 2.2 W or more. The thermal conductivity of the sealingresin 7 can be adjusted by adjusting the amount and material of thefiller. Therefore, a surface resin portion 71, which will be describedlater, is made of a material having an electrical insulating propertyand a thermal conductivity of 2.2 W or more.

The sealing resin 7 covers the entire area of the clips 51 and 52 exceptfor connection portions with the lead frames 30 and 40. Therefore, apart of the sealing resin 7 is also formed on the clips 51 and 52. Thatis, the sealing resin 7 includes the surface resin portion 71 formed onthe clips 51 and 52. The semiconductor device 100 includes the surfaceresin portion 71 so that the clips 51 and 52 are not exposed from thesealing resin 7. The semiconductor device 100 is provided with thesurface resin portion 71, so that the electrical insulation of the clips51 and 52 can be ensured.

The surface resin portion 71 is formed on the surface of the clips 51and 52 opposite to the semiconductor elements 1 and 2. Further, thesurface resin portion 71 is formed on the entire surface of the clips 51and 52 opposite to the semiconductor elements 1 and 2. Therefore, thesecond surface S2 and the opposite surfaces of the clips 51 and 52 thatare opposite to the surfaces facing the semiconductor elements 1 and 2are located at different positions in the Z direction. The surfaces ofthe clips 51 and 52 facing the semiconductor elements 1 and 2 aresurfaces facing the source electrodes 12 and 22.

The surface resin portion 71 has a thickness at least one time theparticle size of the filler. As a result, the sealing resin 7 can havethe surface resin portion 71 containing the filler. That is, the sealingresin portion 7 a can secure electrical insulation while maintaining thethermal conductivity of the filler. In other words, the sealing resin 7can ensure heat dissipation and electrical insulation.

When the thickness of the surface resin portion 71 is about the particlesize of the filler, it can be said that the sealing resin 7 has oneresin layer formed on the clips 51 and 52. Further, it can be said thatthe sealing resin 7 includes the surface resin portion 71 having athickness of one time or more the particle size of the filler.

Further, the surface layer portion 71 preferably has a thickness of 0.2mm or more and 0.6 mm or less. The thickness of the surface resinportion 71 is the thickness in the Z direction. The thickness of thesurface resin portion 71 a can be adjusted by adjusting a size of acavity of a mold.

It is conceivable that the thickness of the surface resin portion 71varies depending on a tolerance of a shape and a thickness the clips 51and 52, a tolerance of solder formed on both sides of the semiconductorelements 1 and 2, and a tolerance of a plate thickness of the leadframes 30 and 40. The inventor examined the thickness of the surfaceresin portion 71 in consideration of these tolerances and the processcapability when molding the sealing resin 7. Then, the inventors couldobtain the result that the thickness of the surface resin portion 71 ispreferably 0.4 mm±0.2 mm. That is, in the semiconductor device 100, bysetting the thickness of the surface resin portion 71 to 0.4 mm±0.2 mm,it is easy to form the surface resin portion 71 containing the filler,and heat dissipation and electrical insulation can be ensured.

The present embodiment adopts the lead frames 30 and 40 having recessedportions recessed from the opposite surface S11, as shown in FIG. 2.Therefore, the sealing resin 7 is also formed between the lead frames 30and 40 and the first surface S1. However, the present disclosure is notonly limited to the above example.

As described above, since the semiconductor device 100 is covered withthe sealing resin 7 without exposing the clips 51 and 52, electricalinsulation can be ensured. Further, since the sealing resin 7 in thesemiconductor device 100 has a thermal conductivity of 2.2 W or more,heat dissipation can be ensured. That is, the semiconductor device 100can secure electric insulation and heat dissipation without providing anelectrically insulating heat dissipating gel or the like on the clips 51and 52. In other words, the semiconductor device 100 can secure electricinsulation and heat dissipation without additional component. Therefore,the semiconductor device 100 does not need to guarantee electricinsulation and heat dissipation on a user side such as a deliverydestination.

Further, as shown in FIG. 3, the heat dissipation characteristics of thesemiconductor device 100 and a semiconductor device of a comparativeexample (hereinafter, simply comparative example) were compared bysimulation. In FIG. 3, the horizontal axis represents the thickness ofthe gel [mm], and the vertical axis represents the thermal resistance [°C./W]. In this simulation, the temperature of the upper surface of thegel was fixed. The gel is a heat dissipation gel having electricinsulation.

The comparative example has a structure in which a semiconductor devicehaving a double-sided heat dissipation structure is insulated with gel.That is, in the comparative example, an electrically insulating heatdissipating gel having a thermal conductivity of 3 W is provided on theheat sink.

Further, the thermal resistance indicates the thermal resistance in thesurface resin portion 71 and the gel. That is, the thermal resistance ofthe semiconductor device 100 indicates the thermal resistance of thesurface resin portion 71 provided on the clips 51 and 52. In a casewhere the gel is provided on the surface resin portion 71, the thermalresistance of the semiconductor device 100 indicates the thermalresistance between the surface resin portion 71 and the gel.

The graph shown by diamond points is a graph showing the heatdissipation characteristics of the comparative example. The graph shownby triangular points is a graph showing the heat dissipationcharacteristics of the semiconductor device 100 in a case where thethermal conductivity of the sealing resin 7 is 3 W and the thickness ofthe surface resin portion 71 is 0.5 mm. The graph shown by circularpoints is a graph showing the heat dissipation characteristics of thesemiconductor device 100 in a case where the thermal conductivity of thesealing resin 7 is 2.2 W and the thickness of the surface resin portion71 is 0.6 mm. The graph shown by square points is a graph showing theheat dissipation characteristics of the semiconductor device 100 in acase where the thermal conductivity of the sealing resin 7 is 1 W andthe thickness of the surface resin portion 71 is 0.5 mm.

The semiconductor device 100 of the present embodiment is not providedwith a gel. Therefore, the thermal resistance of the semiconductordevice 100 is a value at a gel thickness of 0 mm. Further, in thesemiconductor device 100, as preferable examples as described above, thethermal conductivity of the sealing resin 7 is set to 2.2 W or more.

Therefore, it can be seen that the thermal resistance of thesemiconductor device 100 is smaller than about 8° C./W, as shown in thegraph of the circular points and triangular points in FIG. 3. Therefore,it can be seen that the semiconductor device 100 can obtain a thermalresistance equal to or lower than that of the comparative example whenthe thermal conductivity of the sealing resin 7 is set to 2.2 W or more.That is, the semiconductor device 100 can obtain heat dissipation equalto or higher than that of the comparative example when the thermalconductivity of the sealing resin 7 is set to 2.2 W or more. Further,the semiconductor device 100 can obtain heat dissipation equal to orhigher than that of the comparative example when the thermalconductivity of the sealing resin 7 is set to 2.2 W or more, and thethickness of the surface resin portion 71 is set to 0.6 mm or less.

The preferred embodiment of the present disclosure has been describedabove. However, the present disclosure is not limited to the aboveembodiment. Various modifications may be made without departing from thescope and spirit of the present disclosure. First and secondmodifications will be described as the other embodiments below. Theabove-described embodiment and first and second modifications can becarried out individually, but can also be carried out in combination asappropriate. The present disclosure can be performed by variouscombinations without being limited to the combination described in theembodiments.

(First Modification)

As shown in FIG. 4, the semiconductor device 100 may be mounted on aprinted circuit board 200 and attached to a motor 300 via a gel 400. Inthe printed circuit board 200, wiring and pads made of conductivemembers are formed on a substrate made of an electrically insulatingresin or the like. In the semiconductor device 100, the first sourceterminal 31, the first drain terminal 32, and the first signal terminals33 are electrically connected to a pad of the printed board 200 via aconductive member such as solder.

The motor 300 includes, for example, a rotor and a stator, as well as ahousing for accommodating these components. The semiconductor device 100is attached to the housing of the motor 300, for example.

As the motor 300, a motor driven by the semiconductor elements 1 and 2of the semiconductor device 100 can be adopted. In this case, thesemiconductor elements 1 and 2 are switching elements of an inverterthat drives the motor 300. The present embodiment adopts the motor 300as an example of an object to which the semiconductor device 100 isattached. However, the present disclosure is not only limited to theabove example. The semiconductor device 100 may be attached to a load(attached object) driven by the semiconductor elements 1 and 2 asdriving elements.

The gel 400 is provided on the second surface S2. As the gel 400, thegel as described above can be adopted. However, the semiconductor device100 has electric insulation by itself. Therefore, the semiconductordevice 100 does not need to secure electric insulation with the motor300 by the gel 400. Therefore, the gel 400 can be thinner than the gelused in the comparative example.

The semiconductor device 100 can have effects similar to the effects ofthe above embodiment. The semiconductor device 100 may include theprinted circuit board 200, the motor 300, and the gel 400.

(Second Modification)

As shown in FIG. 5, a semiconductor device 110 according to the secondmodification differs from the semiconductor device 100 in thearrangement of the semiconductor elements 1 and 2. In the semiconductordevice 110, the first semiconductor element 1 and the secondsemiconductor element 2 are alternately arranged. That is, in thesemiconductor device 110, the second source terminal 41 is arrangedadjacent to the first signal terminals 33, and the second signalterminals 43 are arranged adjacent to the first source terminal 31. Thesemiconductor device 110 can have effects similar to those of thesemiconductor device 100.

What is claimed is:
 1. A semiconductor device comprising: asemiconductor element having a first surface and a second surfaceopposite from each other, and having a first electrode exposed on thefirst surface and a second electrode disposed on the second surface; alead frame including a mounting portion and a non-mounting portiondivided from the mounting portion, the mounting portion having amounting surface to which the semiconductor element is mounted and thefirst electrode is electrically connected, and an opposite surfaceopposite from the mounting surface; a bridge member having conductivityand electrically connecting the second electrode and the non-mountingportion; and a sealing resin having electric insulation, having athermal conductivity of 2.2 W or more, and covering the semiconductorelement, the lead frame, and the bridge member in a state where theopposite surface of the mounting portion is exposed from the sealingresin, wherein the sealing resin includes, as constituent materials, anelectrically insulating resin and a filler having a higher thermalconductivity than the electrically insulating resin, and has a surfaceresin portion disposed on the bridge member, and the surface resinportion has a thickness of 0.2 mm or more and 0.6 mm or less.